Jennifer McMahon’s latest novel, The One I Left Behind, begins in 1985. Reggie is thirteen years old and a murderer is terrorizing her hometown of Brighton Falls, Connecticut. The serial killer, nicknamed Neptune by the local police and press, is kidnapping and murdering women, leaving their bodies to be found by local police days later. The fourth and final victim is Reggie’s mother Vera. Unlike the other three women, Vera’s body is never found. For years the case is left unsolved, leaving Reggie with no closure.

Twenty five years later in 2010, a woman is found at a homeless shelter and identified as Vera. Vera’s reappearance forces Reggie to face emotions she hasn’t dealt with in years. At the same time, it reopens the unsolved Neptune murder cases, and creates new questions—why was Vera allowed to live, and where has she been all these years? Reggie brings her ailing mother back to their hometown to stay somewhere familiar in hopes that it will make her more comfortable. As the residents of Brighton Falls learn that Vera is alive and in town, the desire to learn the identity of Neptune is renewed. When another woman is kidnapped, Reggie realizes that Neptune has returned and takes matters into her own hands, investigating the murders and new disappearance on her own.

Switching back and forth between Reggie’s childhood, the present, and excerpts from a book about the Neptune serial killer, The One I Left Behind gives readers multiple sides to this mystery, taking readers along for Reggie’s search for the truth about her mother’s disappearance. The One I Left Behind is a thrilling mystery that readers won’t be able to put down.